(1) Field of the Invention
The present invention relates to a high temperature dynamic seal for scramjet engines at the interface between fixed and movable engine hardware.
(2) Prior Art
As supersonic combustion ram jet (scramjet) technology continues to develop, an important goal will be to improve the propulsion system's operability and performance. One method of achieving this goal is to incorporate variable geometry into the engine flowpath design. Variable geometry allows for real time optimization of the engine flowpath lines for varying flight conditions. Incorporating a movable cowl inlet flap is one method of achieving variable geometry in a scramjet engine.
There are many challenges associated with incorporating variable geometry in a scramjet environment. Sealing at the interface between the fixed and movable hardware is one of these challenges. The combination of extreme thermal environment and the pressure differential across this joint makes the seal design solution difficult to identify. The sealing solution must limit overboard leakage of the working fluid (in this case, compressed air) from the engine flowpath so as not to degrade engine performance or cause thermal distress in neighboring hardware. It must accomplish this task in an extremely hostile thermal environment while accommodating the travel of the flap. Local thermal and mechanical distortion in the surrounding hardware must also be accounted for.